In a cabin of a construction machine, farm machine, industrial vehicle or the like or an automobile, a blower type heating apparatus is provided to make a comfortable environmental condition for an operator or driver in winter. For example, a heating apparatus to be installed in a cabin of a construction machine is such that, as shown in FIG. 3, a heater 12 is installed on a floor behind the operator's seat 11 to introduce air from the cabin through both sides of the heater 12, to heat air in the heater 12 and to supply heated air from the front side of the heater and, as shown in FIG. 4, an air conditioner unit 1 is installed on a floor behind the operator's seat to introduce air from the cabin through an inlet 13, to heat it in the air conditioner unit 1 and to supply heated air to the front side of the operator's seat 11 through a space below the operator's seat and to the upper corner of the cabin from the rear side of the operator's seat 11.
In case of a cabin heating apparatus as shown in FIG. 3, however, heated air outlets are provided only at the front side of the heater 12, and therefore the heated air is immediately collected at the upper part of the cabin and a temperature distribution in the cabin is not likely to attain an optimum condition such as a head-cool and feet-warm environment. Also in case of an air conditioner unit as shown in FIG. 4, the environmental condition in the cabin is similar to the above and the air conditioner unit is unlikely to provide such head-cool and feet-warm condition even though the heated air is blown out upwardly from the heated air outlets behind the operator's seat 11 to promote air circulation in the cabin. Such conventional heating apparatuses as described above also have a problem that the operator or driver cannot be relieved from a feeling of coldness at the front part, particularly the parts below the knees, of his body.
An object of the present invention made in view of the above conventional problems is to provide a cabin heating apparatus capable of obtaining an optimum temperature distribution even under winter environmental conditions.